Power flow cyber attacks and perturbation-based defense

Context: An inverter-based microgrid working in islanded mode can suffer cyber- attacks, these can be done against either the local controller or the communication links among the inverters. Secondary control is able to reject those attacks, however, a tertiary control action is necessary in order to stabilize the power flow among the microgrid. Method: Confidence factor technique allows to reject attacks in a microgrid acting directly over the secondary control, however, this technique omits other factor related to the power available. In this case, secondary control was complemented with a tertiary control that includes optimization criteria. Results: An inverter-based microgrid is simulated in Matlab for different scenarios and under cyberattack, this allows checking the correct response of the controller under attacks and the effective powersharing among inverters. Conclusions: The tertiary control allows stabilizing the active power of the system after the rejection of a cyber-attack by the secondary control. Each inverter supplies active power according to its máximum power rating without affecting the stability of the whole system.

Download Full-text

An Interior-Point Solver for Optimal Power Flow Problem Considering Distributed FACTS Devices

10.36227/techrxiv.12307553 ◽

2020 ◽

Author(s):

Bo Liu ◽

Lawryn Edmonds ◽

hang zhang ◽

Hongyu Wu

Keyword(s):

Interior Point ◽

Cyber Security ◽

Power Flow ◽

Optimal Power Flow ◽

Economic Benefits ◽

Transmission System ◽

Cyber Attacks ◽

Facts Devices ◽

Optimal Power ◽

Ac Transmission

In this paper, we propose an AC optimal power flow (ACOPF) model considering distributed flexible AC transmission system (D-FACTS) devices, in which the reactance of D-FACTS equipped lines are introduced as decision variables. This is motivated by increasing interests in using D-FACTS devices to address system operational and cyber-security concerns. First, D-FACTS devices can be incorporated in real-time operations for economic benefits such as managing power congestions and reducing system losses. Second, D-FACTS devices can be utilized by moving target defense (MTD), an emerging concept against cyber-attacks, to prevent attackers from knowing true system configurations. Therefore, system operators can use the proposed ACOPF model to achieve economic benefits and provide the setpoints of D-FACTS devices for MTD at the same time. In addition, we rigorously derive the gradient and Hessian matrices of the objective function and constraints, which are further used to build an interior-point solver of the proposed ACOPF. Numerical results on the IEEE 118-bus transmission system show the validity of the proposed ACOPF model as well as the efficacy of the interior-point solver in minimizing system losses and generation costs. <br>

Download Full-text

An Interior-Point Solver for Optimal Power Flow Problem Considering Distributed FACTS Devices

10.36227/techrxiv.12307553.v1 ◽

2020 ◽

Author(s):

Bo Liu ◽

Lawryn Edmonds ◽

hang zhang ◽

Hongyu Wu

Keyword(s):

Interior Point ◽

Cyber Security ◽

Power Flow ◽

Optimal Power Flow ◽

Economic Benefits ◽

Transmission System ◽

Cyber Attacks ◽

Facts Devices ◽

Optimal Power ◽

Ac Transmission

In this paper, we propose an AC optimal power flow (ACOPF) model considering distributed flexible AC transmission system (D-FACTS) devices, in which the reactance of D-FACTS equipped lines are introduced as decision variables. This is motivated by increasing interests in using D-FACTS devices to address system operational and cyber-security concerns. First, D-FACTS devices can be incorporated in real-time operations for economic benefits such as managing power congestions and reducing system losses. Second, D-FACTS devices can be utilized by moving target defense (MTD), an emerging concept against cyber-attacks, to prevent attackers from knowing true system configurations. Therefore, system operators can use the proposed ACOPF model to achieve economic benefits and provide the setpoints of D-FACTS devices for MTD at the same time. In addition, we rigorously derive the gradient and Hessian matrices of the objective function and constraints, which are further used to build an interior-point solver of the proposed ACOPF. Numerical results on the IEEE 118-bus transmission system show the validity of the proposed ACOPF model as well as the efficacy of the interior-point solver in minimizing system losses and generation costs. <br>

Download Full-text

Rule-Based Detection of False Data Injections Attacks against Optimal Power Flow in Power Systems

Sensors ◽

10.3390/s21072478 ◽

2021 ◽

Vol 21 (7) ◽

pp. 2478

Author(s):

Sani Umar ◽

Muhamad Felemban

Keyword(s):

Power Generation ◽

Power Systems ◽

Cyber Security ◽

Power Flow ◽

Optimal Power Flow ◽

Cyber Attacks ◽

Rule Based ◽

Generation Cost ◽

The Cost ◽

The Impact

Cyber-security of modern power systems has captured a significant interest. The vulnerabilities in the cyber infrastructure of the power systems provide an avenue for adversaries to launch cyber attacks. An example of such cyber attacks is False Data Injection Attacks (FDIA). The main contribution of this paper is to analyze the impact of FDIA on the cost of power generation and the physical component of the power systems. Furthermore, We introduce a new FDIA strategy that intends to maximize the cost of power generation. The viability of the attack is shown using simulations on the standard IEEE bus systems using the MATPOWER MATLAB package. We used the genetic algorithm (GA), simulated annealing (SA) algorithm, tabu search (TS), and particle swarm optimization (PSO) to find the suitable attack targets and execute FDIA in the power systems. The proposed FDIA increases the generation cost by up to 15.6%, 45.1%, 60.12%, and 74.02% on the 6-bus, 9-bus, 30-bus, and 118-bus systems, respectively. Finally, a rule-based FDIA detection and prevention mechanism is proposed to mitigate such attacks on power systems.

Download Full-text